Discernment of grape rootstocks base on their response to salt stress using selected characteristics in combination with chemometric tools

In the present study, first, the 19 parameters of 21 grapevine rootstocks under salinity were measured. Then chemometrics methods including principal component analysis (PCA) and quadratic discriminant analysis (QDA) were used to select the most significant and responsible characteristics for discrimination of grapevine rootstocks. For QDA, the 19 parameters were arranged in 4 sets. The first set includes total phenolic content, total flavonoid content, total anthocyanin content, and free radicals scavenging activity showed 88.10% correct classification. The second set (phenylalanine ammonia-lyase, superoxide dismutase, ascorbate peroxidase, and catalase activity) had 94.64% correct classification. Na+, K+, K+/Na+, electrolyte leakage, and malondialdehyde content parameters were in the third set and had 89.29% correct discrimination. The best discrimination was obtained by the fourth set, including total carbohydrate content, total protein content, proline, glycine-betaine, chlorophyll a, and chlorophyll b characteristics with 100% correct discrimination.